The company has invested pound200 million ($271 million) in the project which includes a production facility in Mildenhall and a testing site in Elmsett, both in eastern England, the Ministry of Defence said in a statement.

"Four years on from Russia's full-scale invasion of Ukraine, this factory delivers what matters: secure supply, secure resource, and sustained support for Ukraine," said director of Ukrspecsystems UK Rory Chamberlain.

Other Ukrainian defence companies have already opened or have plans for production sites elsewhere in Europe, such as in Denmark and Germany.

It was unclear what type of drones would be produced at the UK factory but the company, founded in 2014, notably manufactures surveillance drones.

The UK has already purchased 80 of these for Ukrainian forces.

"Ukrspecsystems' new factory is a vote of confidence in UK support and underlines the deepening cooperation between our nations' defence industries," added British Armed Forces Minister Luke Pollard, who inaugurated the site on Wednesday.